The situation was as disturbing as it was cruel: three girls, trapped in a bedroom tainted with urine and feces, a piece of drywall nailed across the door. The people responsible, police say, were their parents.

A 4-year-old, the oldest, scaled the drywall. She ran to a neighbor, who tore down the makeshift barricade and rescued her 2-year-old and 6-month-old sisters, who were naked and filthy. Their parents, Christina Moore and John Robey, were found in an adjacent room in the single-family home on Loft Court in Bristow on Saturday, according to court records released Tuesday.

The neighbor could not wake the couple because they were out cold, the records say. Officers said they found prescription narcotics, smoking devices and needles in the room.

It is a discovery that has led to felony child abuse charges against Moore, 26, and Robey, 33, who were being held without bond in Prince William County. It is the second time Moore has been charged in connection with her children; she lost custody of her twin sons six years ago after she fell asleep and lost track of the boys, who wandered to the side of a busy road.

Law enforcement and social services officials said they are nearly powerless to protect children born to a parent who has faced earlier neglect charges associated with other children. There must be evidence of abuse before officials can intervene, Commonwealth’s Attorney Paul B. Ebert said.

Those who know Moore and Robey said they have struggled with drugs and financial problems, and Ebert said he thinks this case was related to substance abuse. The girls appeared to have been contained in the room for less than a day and were not physically harmed, police said.

Prince William police said the Loft Court neighbor tore down a drywall “half-wall” Saturday to get to the children. She bathed them there and took them to her home, then called police. Officers said the room and its windows were covered in feces, according to a criminal complaint.

“This is a very serious case,” Ebert said. “From [Moore’s] history, it is clear she has no business being a parent or guardian.”

An attorney for Moore declined to comment. It could not be determined whether Robey had obtained a lawyer.

The three girls were turned over to officials with Prince William’s Child Protective Services, who placed them in an emergency foster care home. Janine Sewell, director of the county’s Department of Social Services, said she could not give details about the case or say whether there were previous complaints about Moore or Robey. She said the department was cooperating with police.

Parents dealing with substance abuse are often able to conceal problems in their homes, Sewell said. “With young children, it is more up to a family member to report a situation, because nobody else is seeing them in school or out in public,” she said.

Court records show that Moore was arrested in June 2005 when her sons, then 22 months old, managed to leave a junkyard trailer where she was sleeping and toddled out to the shoulder of Route 234 in Dumfries. A motorist pulled over and flagged down a Virginia State Police trooper.

Chuck Feldbush, a retired Prince William police detective, investigated the case. He said that Moore said she put a bungee cord across the trailer’s door, but the children managed to get out in the morning while she was sleeping.

“The kids were in terrible shape,” Feldbush said Tuesday. “They were dirty, and they were playing by the side of a major roadway. It was just tragic to see that kind of thing. They could have been taken or killed.”

The boys were placed in the custody of their father, Daniel Tincher, who has raised them since. Tincher, 25, said he lost contact with Moore for several years before she later sought visitation rights.

The Loft Court home, a two-story gray house in the quiet Braemar community, belongs to Moore’s father. Kim Pickard, a neighbor and friend of his, said Christina Moore grew up there.

Tincher said his sons, now 7, spent weekends at the house — and reported serious problems. The boys said Moore would visit the same junkyard and leave all five children in the car. They also said she often failed to supervise them, Tincher said.

Tincher said he stopped allowing Moore and Robey to take his children about a year ago. Tincher said he told social services officials about problems at the Bristow home, including an instance when one of his boys arrived home with a welt Tincher thought had been caused by a belt.

When the boys saw a TV news report about their mother’s arrest, Tincher said, they said they also had been placed behind a drywall barricade at her home.

“Her problem is trying to contain the kids while not watching them,” Tincher said. “She just wants to put them away to the side so she can do what she wants to do.”

Moore’s father could not be reached Tuesday. Robey’s family could not be reached.

Tincher said Moore has struggled with prescription narcotics and had been involved in using drugs. Court records from her 2005 case show that she admitted using cocaine and heroin while on probation at the time.

Matthew Cockrill, a friend of the couple’s who once dated Moore, said he was at the home about a month ago and didn’t notice anything out of the ordinary. The girls seemed happy and well cared for, Cockrill said, and toys were all over the home. But the house was sparsely furnished, Cockrill said, and Moore looked as if she was “going through a tough time.”

“I can’t believe something like this would happen,” said Cockrill. He said he thinks Robey is a good person. “He doesn’t seem like the kind of person who would drywall his kids in a room.”